The invention relates to a heating facility for a motor vehicle component to be heated, in particular for a valve or a washing nozzle of a shield cleaning system having an electric heating element.
Such heating facilities serve for maintaining the corresponding component at a temperature above 0xc2x0 C. and are known in practice. In such cases, the heating element is usually fastened directly to the washing nozzle or to the valve of the shield cleaning system. Fastening is usually carried out by inserting the heating element into a recess of the component. The component to be heated and the heating element are subsequently sealed together. For this purpose, it is necessary to design receiving devices for each of the components and to adapt the heating element accordingly. The heating element is designed selectively as a resistance element or as a PTC element. The advantage of designing the heating element as PTC element is that its heating capacity rises with a falling temperature. This makes it possible to control the heating in a particularly simple way.
One disadvantage of the known heating facility is that the fastening of the heating element to the component to be heated is very complicated. Furthermore, the component to be heated is heated by the heating element in only a very small region. A high temperature and therefore a cost-intensive thermally resistant design of the components are necessary for this purpose.
The problem on which the invention is based is to provide a heating facility of the type initially mentioned, in such a way that it can be mounted in a very simple way and is suitable for heating highly diverse components.
This problem is solved, according to the invention, by arranging the heating element within a receptacle provided for fastening to the component.
By virtue of this heating facility, the heating element forms, with the receptacle, a premountable structural unit which can be produced and tested independently of the component. Direct contact of the heating element with the component to be heated is avoided by arranging the heating element within the receptacle. Since the heating facility according to the invention is provided with a large heat transmission area, damage to the component to be heated, due to local overheating, is ruled out. The heating facility according to the invention is therefore suitable for heating highly diverse and less thermally resistant components. By virtue of the invention, therefore, there is no need for the heating element to be adapted to each of the components. The components to be heated may, for example, be valves and washing nozzles or else a door lock of the motor vehicle. If a particularly high heating capacity is necessary for the corresponding component, a plurality of heating facilities according to the invention can also be fastened to the component. Furthermore, the mounting of the heating facility according to the invention is simplified, since there is no need for it to be sealed together with the component. The receptacle of the heating facility according to the invention can, for example, simply be inserted into a correspondingly designed recess of the component to be heated, and clamped tight, firmly bonded or secured by snapping.
Advantageously, the heating element is a resistance or PTC element.
The heating facility according to the invention can be inserted in a very simple way in a heating well of the component to be heated, if the receptacle is of cylindrical design. Moreover, virtually the entire heating capacity emitted by the heating element is thereby supplied to the component.
The heating facility according to the invention can be manufactured particularly cost-effectively if the heating element is held in the receptacle by means of a sealing compound. Moreover, manufacture can thereby be automated.
According to another advantageous development of the invention, the receptacle is heated particularly uniformly if the receptacle is manufactured from metal. On account of the high thermal conductivity and thermal capacity of the metal, the heating capacity passes particularly uniformly to the component to be heated. Furthermore, the mounting of the heating element in the receptacle thereby becomes particularly simple.
According to another advantageous development of the invention, the receptacle has particularly high thermal conductivity and can be manufactured particularly cost-effectively by the deep-drawing method if the receptacle is manufactured from aluminum.
The heating facility according to the invention is particularly cost-effective if the receptacle is manufactured from plastic. In the simplest case, the receptacle consists of sealing compound.
If the component to be heated consists of plastic, in another advantageous embodiment injection molding is carried out directly around the heating element, in that the heating element is inserted into the injection mold when the component to be heated is being produced.